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Shaping for Optical Direct-Detection Links
Shaping for Optical Direct-Detection Links
상세정보
- 자료유형
- 학위논문 서양
- 최종처리일시
- 20260202103137
- ISBN
- 9798311963169
- DDC
- 621.3
- 서명/저자
- Shaping for Optical Direct-Detection Links
- 발행사항
- [Sl] : Stanford University, 2025
- 발행사항
- Ann Arbor : ProQuest Dissertations & Theses, 2025
- 형태사항
- 197 p
- 주기사항
- Source: Dissertations Abstracts International, Volume: 86-12, Section: B.
- 주기사항
- Advisor: Kahn, Joseph.
- 학위논문주기
- Thesis (Ph.D.)--Stanford University, 2025.
- 초록/해제
- 요약There is a clear and pressing need for energy-efficient modulation methods to enable the next generation of optical direct detection-based links. Geometric and probabilistic shaping are two classes of techniques that can improve receiver sensitivity and dispersion tolerance for these optical links. This dissertation advances the theory and practice of geometric shaping and probabilistic shaping for several types of direct detection receivers, including the standard direct detection receiver, the Stokes vector receiver, and the Kramers-Kronig receiver.Chapter 1 introduces the broad fields of communications and information theory before more narrowly focusing on direct detection methods in optical communications.Chapter 2 discusses intra-data center links, which are subject to transmission impairments that pose challenges for efficient scaling of per-wavelength data rates beyond 100 Gb/s. Limited electrical and optical component bandwidths, limited data converter resolution, and component nonlinearity induce significant signal-dependent distortion, degrading receiver sensitivity (RS) and chromatic dispersion tolerance. Chapter 2 presents a geometric shaping (GS) scheme that optimizes transmitted intensity levels based on symbol-error statistics observed at the receiver. The proposed GS scheme adjusts these levels to achieve substantially equal symbol-error probabilities at all decision thresholds. The scheme enables the levels most affected by signal-dependent distortion to be detected with the same reliability as other levels, thereby increasing the effectiveness of linear or nonlinear equalization techniques. This can be exploited to improve RS and extend transmission distance for a fixed equalization scheme or, alternatively, to reduce the complexity of signal processing needed to achieve a target RS or transmission distance. For example, in 200 Gb/s PAM links, GS and 21-tap linear equalization achieves RS and reach similar to uniform level spacing and Volterra nonlinear equalization with 21 linear and 3 second-order taps.Chapter 3 discusses shaping with continuous and discrete channel input distributions for the Stokes vector receiver (SVR). We use the high-rate continuous approximation (HCA) to derive tight analytical approximations to the optimal continuous input distribution at high signal-to-noise ratio (SNR). The HCA analysis finds that an exponential distribution in the intensity (corresponding to the Stokes parameter S0) is the optimal continuous input distribution for thermal noise-limited and amplifier noise-limited SVRs, providing ultimate shaping gains of 1.056 dB and πe/6 ≈ 1.533 dB, respectively. We also perform numerical studies of discrete channel input distributions obtained using the Blahut-Arimoto method or by sampling analytically derived continuous distributions. We find that a sampled exponential distribution in the intensity provides 0.078 dB and 0.165 dB higher shaping gains than a sampled Gaussian distribution of the SV in the thermal noise-limited and amplifier noise-limited regimes, respectively. We also compare the performance of the SVR to that of a dual-polarization coherent receiver. We show that, owing to noise enhancement, the SVR incurs an SNR penalty of about 5.5 dB with respect to a coherent system that modulates three of the four available degrees of freedom.Chapter 4 presents a comprehensive overview of probabilistic shaping distributions for optical communications in the high-rate regime. Probabilistic shaping is widely employed in local oscillator-based coherent optical systems to improve receiver sensitivity and provide rate adaptation.
- 일반주제명
- Electrical engineering
- 기타저자
- Stanford University.
- 기본자료저록
- Dissertations Abstracts International. 86-12B.
- 전자적 위치 및 접속
- 로그인 후 원문을 볼 수 있습니다.
MARC
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■00520260202103137
■006m o d
■007cr#unu||||||||
■020 ▼a9798311963169
■035 ▼a(MiAaPQ)AAI31974659
■035 ▼a(MiAaPQ)Stanfordvw573sb2840
■040 ▼aMiAaPQ▼cMiAaPQ
■0820 ▼a621.3
■1001 ▼aLiang, Ethan Mark.
■24510▼aShaping for Optical Direct-Detection Links
■260 ▼a[Sl]▼bStanford University▼c2025
■260 1▼aAnn Arbor▼bProQuest Dissertations & Theses▼c2025
■300 ▼a197 p
■500 ▼aSource: Dissertations Abstracts International, Volume: 86-12, Section: B.
■500 ▼aAdvisor: Kahn, Joseph.
■5021 ▼aThesis (Ph.D.)--Stanford University, 2025.
■520 ▼aThere is a clear and pressing need for energy-efficient modulation methods to enable the next generation of optical direct detection-based links. Geometric and probabilistic shaping are two classes of techniques that can improve receiver sensitivity and dispersion tolerance for these optical links. This dissertation advances the theory and practice of geometric shaping and probabilistic shaping for several types of direct detection receivers, including the standard direct detection receiver, the Stokes vector receiver, and the Kramers-Kronig receiver.Chapter 1 introduces the broad fields of communications and information theory before more narrowly focusing on direct detection methods in optical communications.Chapter 2 discusses intra-data center links, which are subject to transmission impairments that pose challenges for efficient scaling of per-wavelength data rates beyond 100 Gb/s. Limited electrical and optical component bandwidths, limited data converter resolution, and component nonlinearity induce significant signal-dependent distortion, degrading receiver sensitivity (RS) and chromatic dispersion tolerance. Chapter 2 presents a geometric shaping (GS) scheme that optimizes transmitted intensity levels based on symbol-error statistics observed at the receiver. The proposed GS scheme adjusts these levels to achieve substantially equal symbol-error probabilities at all decision thresholds. The scheme enables the levels most affected by signal-dependent distortion to be detected with the same reliability as other levels, thereby increasing the effectiveness of linear or nonlinear equalization techniques. This can be exploited to improve RS and extend transmission distance for a fixed equalization scheme or, alternatively, to reduce the complexity of signal processing needed to achieve a target RS or transmission distance. For example, in 200 Gb/s PAM links, GS and 21-tap linear equalization achieves RS and reach similar to uniform level spacing and Volterra nonlinear equalization with 21 linear and 3 second-order taps.Chapter 3 discusses shaping with continuous and discrete channel input distributions for the Stokes vector receiver (SVR). We use the high-rate continuous approximation (HCA) to derive tight analytical approximations to the optimal continuous input distribution at high signal-to-noise ratio (SNR). The HCA analysis finds that an exponential distribution in the intensity (corresponding to the Stokes parameter S0) is the optimal continuous input distribution for thermal noise-limited and amplifier noise-limited SVRs, providing ultimate shaping gains of 1.056 dB and πe/6 ≈ 1.533 dB, respectively. We also perform numerical studies of discrete channel input distributions obtained using the Blahut-Arimoto method or by sampling analytically derived continuous distributions. We find that a sampled exponential distribution in the intensity provides 0.078 dB and 0.165 dB higher shaping gains than a sampled Gaussian distribution of the SV in the thermal noise-limited and amplifier noise-limited regimes, respectively. We also compare the performance of the SVR to that of a dual-polarization coherent receiver. We show that, owing to noise enhancement, the SVR incurs an SNR penalty of about 5.5 dB with respect to a coherent system that modulates three of the four available degrees of freedom.Chapter 4 presents a comprehensive overview of probabilistic shaping distributions for optical communications in the high-rate regime. Probabilistic shaping is widely employed in local oscillator-based coherent optical systems to improve receiver sensitivity and provide rate adaptation.
■590 ▼aSchool code: 0212.
■650 4▼aElectrical engineering
■690 ▼a0544
■71020▼aStanford University.
■7730 ▼tDissertations Abstracts International▼g86-12B.
■790 ▼a0212
■791 ▼aPh.D.
■792 ▼a2025
■793 ▼aEnglish
■85640▼uhttp://www.riss.kr/pdu/ddodLink.do?id=T17357141▼nKERIS▼z이 자료의 원문은 한국교육학술정보원에서 제공합니다.


